Confusion among "width", "height" and "r" attributes?

Question

If I specify the value of "r" in "circle" tag, then what is "width" & "height" doing in "svg" tag?

Answer 1

Width and Height are attributes of SVG element. They define the area in which to draw the circle shape.

Answer 2

You don't have width, height and r, but: cx, cy and r. Cx and cy define the coordinates of the circle and the r defines the radius

Answer 3

The "cx" and "cy" values refer to the given distance from the origin of the user coordinate system along the relevant axis. Additionally, "r" refers to the radius of the circle.